“It’s a World War II story we’ve never seen before,” says writer-producer Grant Heslov about The Monuments Men, the Feb. 7 Columbia Pictures release directed by George Clooney, his longtime filmmaking partner. Clooney stars alongside a tantalizing name cast that also includes Matt Damon, Bill Murray, CateBlanchett, John Goodman, Jean Dujardin, Bob Balaban, and Hugh Bonneville of “Downton Abbey.”

The Monuments Men were a group of seven museum directors, curators and art historians recruited to rescue art masterworks stolen by the Nazis and ultimately return them to their rightful owners. None were professional soldiers, but they willingly courted danger by going behind enemy lines to fulfill their cultural mission. Clooney plays Frank Stokes, a fictional surrogate for George Stout, then an art conservationist at Harvard’s Fogg Art Museum; Damon is James Granger, based on James Rorimer, a curator at New York’s Metropolitan Museum and founder of the Cloisters; and Blanchett is Claire Simone, based on Rose Valland, a courageous Frenchwoman who managed the Jeu de Pomme during the occupation of Paris.

Heslov and Clooney adapted the screenplay from Robert M. Edsel and Bret Witter’s 2009 book The Monuments Men: Allied Heroes, Nazi Thieves, and the Greatest Treasure Hunt in History. As Heslov recalls, “I picked the book up at a bookstore—I was just browsing and it seemed interesting… And about a year later George and I were talking about what we wanted to do next and it came up in conversation, and we decided: Yeah, it would make a really great film.”

Heslov continues, “We were looking to do something without much cynicism. We’d just come off doing The Ides of March, which obviously is a very cynical look at the world. This just fit the bill for us—and it’s an unbelievably great story.”

The writer-producer admits that with such a “monumental” adventure saga, “you have to take some license because it’s so big. You are anchored to certain pivotal points because there are historical moments you can’t mess around with. But the spirit of the story is very intact—it’s the spirit of the time and the book and the people that we spoke to.”

As producers, Heslov and Clooney are often drawn to real-life stories; their resume includes the Oscar-nominated Edward R. Murrow drama Good Night, and Good Luck, The Men Who Stare at Goats, and last year’s Oscar Best Picture winner, Argo. What’s behind the attraction? “George’s father was a newsman and that colors his world,” Heslov notes. “And his father is a big history buff. For me, I like stories that happened, or that have some element of truth. I just find them fascinating. Not to the exclusion of completely fictional stories, but some of the better underlying material you read comes from stuff that’s based in fact.”

One can’t help thinking that the name George Clooney is a magnet for securing the kind of A-level cast The Monuments Men boasts, but Heslov insists, “Everything starts with the script—hopefully people are attracted to that. And with George playing one of the leads, that makes it easier to cast. But that’s the case with any film—you get the first actor and then everything else falls into place. I like to think that our track record helps us attract a good cast.”

Clooney and Heslov are also producers of another upcoming release with an all-star cast—The Weinstein Company’s August: Osage County, the film adaptation of the Pulitzer Prize-winning comedy-drama starring Meryl Streep, Julia Roberts, Ewan McGregor, Chris Cooper, Sam Shepard and Juliette Lewis. Heslov explains, “When the rights became available to the play, George and I chased it. And we couldn’t get it because Harvey [Weinstein] already had the option because he had been involved with the play. But subsequently Harvey came back to us and said: Hey, you guys want to produce? That was great, because we really love that play. We loved the idea of doing a film that was heavily female, because we often don’t do that. It hasn’t really been a conscious choice—the things that we’ve done just haven’t had a lot of female roles.”

So how does Heslov feel about having two potential awards contenders in the offing? “You just try to make the best film you can make,” he counters. “If you focus on that stuff, you get yourself into trouble. Our goal with Monuments Men was to make a big, entertaining film, and I think we succeeded. And August: Osage is just a fantastic experience—I think that film is going to do very well.”

Heslov and Clooney first met in an acting class when they were struggling performers and have remained friends ever since. (They actually appeared together on an episode of “The Facts of Life,” on which Clooney was a regular and Heslov was a guest player.) As Clooney enjoyed his breakout on “ER,” Heslov was taking supporting roles in films like True Lies, Congo and Dante’s Peak. Their first collaboration as producers was the HBO series “K Street,” followed by Good Night, and Good Luck in 2005.

Looking back on how far he and his partner have come, Heslov calls the journey “amazing. Once in while, we’ll go: Jesus, this is wild. Because we really did start out, both of us, with nothing, in terms of our careers. So it does put a big smile on your face.”

Heslov confesses that he misses his performing days, “because acting’s a lot of fun. It’s completely different than the producing or writing or directing side. With acting, you’re just concerned about one thing, and that’s your role and your character’s part of the whole. And you have no idea what’s going on to make all this happen. In retrospect, it’s a very cushy job.

“But I have a part in The Monuments Men. A guy who was supposed to play a doctor couldn’t make it on the day we were shooting—he had a medical issue with his wife—and we were going to recast it. And George said: Why don’t you just play it? It was fun, we had a great time.”

Heslov says he knew Clooney would be a good director “before he ever directed a film. About 25 years ago we were trying to get a film made, and he directed a five or ten-minute piece and I could tell then he had a good sense of it. On Confessions of a Dangerous Mind[Clooney’s directing debut], he had such a deft hand. When you work with George, he knows exactly what he wants. There’s always a very strong point of view.”

Those strong convictions, however, don’t result in on-set tension. “We both feel it shouldn’t be a drag to go to work. He tries to keep things very light, except when you have to be really serious about the shooting. He doesn’t work long days—he doesn’t believe in that. We do a lot of prep to make sure we can keep our days as short as possible. It’s important for us that everybody has a good time.”

As to how their alliance works, Heslov observes, “We have similar tastes, but we challenge each other. There’s qualities in my work style that are the opposite of his, and that makes for a good partnership.”

Heslov adds, “If it’s a film he’s directing, there’s some division in what we do. But if it’s something like August: Osage County, not really. We’re both on the set together, we get on the calls together, we give notes together—we pretty much try to speak as one voice. Otherwise it can get annoying or confusing for a filmmaker. We’re pretty aligned in that case.”

After three nominations (twice for writing, once for producing), Heslov finally took home Oscar gold this past February as one of the producers of Argo. Thanks to Ben Affleck’s omission in the directing race, the Best Picture win wasn’t a sure thing. “But when you think about it, we did win every single possible award—the BAFTAs, the Golden Globes, the Broadcast Critics. Yet people were still saying we were the underdog, which was great, because I’d much rather be in that position. I think being the frontrunner is a tough place to be."